A NOVEL HYDROCARBON, THYLIDENETRICYCLO[7.1.1.0(2,7)]UNDECA-2,4,6-TRIENE - SYNTHESIS OF BENZOPINANE SKELETON VIA DI-PI-METHANE REARRANGEMENTOF BENZONORBORNADIENE SYSTEM

The [4 + 2] cycloadduct 17 of hylidene-1,2,3,4-tetrahydro-1,3-methanon aphthalene and 4-phenyl-4H-1,2,4-triazole-3,5-dione (PTAD) was subject ed to a tripler-sensitized di-pi-methane rearrangement. Hydrolysis of the resulting urazol 18 gave the hydrocarbon 7. Hydrolysis of 18 at lo wer base concentrations led to isomeric stable semicarbazides 24 and 2 5, which were submitted NiO2 or MnO2, oxidation, to give the target co mpound 7, and oxidation products 26 and 27.